Control

The GAMS Matlab Control API provides a Matlab programming interface to the General Algebraic Model System (GAMS). GAMS Matlab Control API objects allow a convenient way to exchange input data and model results with in-memory representation of data (Database), and to create and run GAMS models (Job) that can be customized by GAMS options (Options). Furthermore, they introduce a way to solve a sequence of closely related model instances in a more efficient way (ModelInstance).

Note
If you only want to exchange data between Matlab and GAMS, use GAMS Transfer Matlab as it is very likely to be more efficient than GAMS Matlab Control API in case of exchanging very large data sets.

The underlying GAMS engine relies to some extent on file based communication (e.g. the listing file) and other unmanaged resources. Since the GAMS Matlab Control API is based on the GAMS Java API, the use of external resources in the Java environment requires special attention. Hence, some objects need to be properly disposed before the Java garbage collector does its job.

A GAMS program can include other source files (e.g. $include), load data from GDX files (e.g. $GDXIN or execute_load), and create PUT files. All these files can be specified with a (relative) path and therefore an anchor into the file system is required. The base object Workspace manages the anchor to the file system.

With the exception of Workspace the objects in the gams package cannot be accessed across different threads unless the instance is locked. The classes themselves are thread safe and multiple objects of the class can be used from different threads (see below for restrictions on solvers that are not thread safe within the ModelInstance class).

Note
If you use multiple instances of the Workspace in parallel, you should avoid using the same working directory. Otherwise you may end up with conflicting file names.

Currently only Cplex, Gurobi, and SoPlex fully utilize the power of solving ModelInstances. Some solvers will not work in a multi-threaded application using ModelInstances. For some solvers this is unavoidable because the solver library is not thread safe (e.g. MINOS). Moreover, ModelInstances are not available for quadratic model types (QCP, MIQCP, RMIQCP).

This version of the GAMS Matlab Control API also does not provide support for the following GAMS components: acronyms, GAMS compilation/execution errors, structured access to listing file, and solver options.

To get started, see Getting Started.

New Class Names

With GAMS 46 the GAMS Matlab Control API has been restructured and classes have been renamed. The following lists a mapping of old to new class names:

  • GAMS.AbstractRunParameters: gams.control.AbstractRunParameters
  • GAMS.GAMSCheckpoint: gams.control.Checkpoint
  • GAMS.GAMSDatabase: gams.control.Database
  • GAMS.GAMSDatabaseDomainViolation: gams.control.DatabaseDomainViolation
  • GAMS.GAMSEngineConfiguration: gams.control.engine.Configuration
  • GAMS.GAMSEngineJob: gams.control.engine.Job
  • GAMS.GAMSEngineJobBuilder: gams.control.engine.JobBuilder
  • GAMS.GAMSEngineRunParameters: gams.control.engine.RunParameters
  • GAMS.GAMSEquation: gams.control.Equation
  • GAMS.GAMSEquationRecord: gams.control.EquationRecord
  • GAMS.GAMSGlobals: gams.control.Globals
  • GAMS.DebugLevel: gams.control.globals.DebugLevel
  • GAMS.UpdateAction: gams.control.globals.UpdateAction
  • GAMS.ModelStat: gams.control.globals.ModelStat
  • GAMS.SolveStat: gams.control.globals.SolveStat
  • GAMS.SetType: gams.control.globals.SetType
  • GAMS.VarType: gams.control.globals.VarType
  • GAMS.EquType: gams.control.globals.EquType
  • GAMS.ArchType: gams.control.globals.ArchType
  • GAMS.OSType: gams.control.globals.OSType
  • GAMS.GAMSJob: gams.control.Job
  • GAMS.GAMSModelInstance: gams.control.ModelInstance
  • GAMS.SymbolUpdateType: gams.control.globals.SymbolUpdateType
  • GAMS.GAMSModelInstanceOpt: gams.control.ModelInstanceOpt
  • GAMS.GAMSModifier: gams.control.Modifier
  • GAMS.GAMSOptions: gams.control.Options
  • GAMS.ZeroResRep: gams.control.options.ZeroResRep
  • GAMS.TraceOpt: gams.control.options.TraceOpt
  • GAMS.TFormat: gams.control.options.TFormat
  • GAMS.SysOut: gams.control.options.SysOut
  • GAMS.Sys11: gams.control.options.Sys11
  • GAMS.Sys10: gams.control.options.Sys10
  • GAMS.Suppress: gams.control.options.Suppress
  • GAMS.SuffixAlgebraVars: gams.control.options.SuffixAlgebraVars
  • GAMS.SuffixDLVars: gams.control.options.SuffixDLVars
  • GAMS.StringChk: gams.control.options.StringChk
  • GAMS.strictSingleton: gams.control.options.strictSingleton
  • GAMS.StepSum: gams.control.options.StepSum
  • GAMS.SolveOpt: gams.control.options.SolveOpt
  • GAMS.SolveLink: gams.control.options.SolveLink
  • GAMS.SolPrint: gams.control.options.SolPrint
  • GAMS.ShowOSMemory: gams.control.options.ShowOSMemory
  • GAMS.SavePoint: gams.control.options.SavePoint
  • GAMS.Replace: gams.control.options.Replace
  • GAMS.ReferenceLineNo: gams.control.options.ReferenceLineNo
  • GAMS.PyMultInst: gams.control.options.PyMultInst
  • GAMS.PutNR: gams.control.options.PutNR
  • GAMS.ProcTreeMemMonitor: gams.control.options.ProcTreeMemMonitor
  • GAMS.PreviousWork: gams.control.options.PreviousWork
  • GAMS.PrefixLoadPath: gams.control.options.PrefixLoadPath
  • GAMS.PageContr: gams.control.options.PageContr
  • GAMS.On115: gams.control.options.On115
  • GAMS.NoNewVarEqu: gams.control.options.NoNewVarEqu
  • GAMS.MIIMode: gams.control.options.MIIMode
  • GAMS.LstTitleLeftAligned: gams.control.options.LstTitleLeftAligned
  • GAMS.LogLine: gams.control.options.LogLine
  • GAMS.Listing: gams.control.options.Listing
  • GAMS.Keep: gams.control.options.Keep
  • GAMS.IntVarUp: gams.control.options.IntVarUp
  • GAMS.InteractiveSolver: gams.control.options.InteractiveSolver
  • GAMS.ImplicitAssign: gams.control.options.ImplicitAssign
  • GAMS.HoldFixedAsync: gams.control.options.HoldFixedAsync
  • GAMS.HoldFixed: gams.control.options.HoldFixed
  • GAMS.gdxUels: gams.control.options.gdxUels
  • GAMS.gdxConvert: gams.control.options.gdxConvert
  • GAMS.gdxCompress: gams.control.options.gdxCompress
  • GAMS.FreeEmbeddedPython: gams.control.options.FreeEmbeddedPython
  • GAMS.ForceWork: gams.control.options.ForceWork
  • GAMS.Filtered: gams.control.options.Filtered
  • GAMS.FileCase: gams.control.options.FileCase
  • GAMS.FDOpt: gams.control.options.FDOpt
  • GAMS.ExecMode: gams.control.options.ExecMode
  • GAMS.ErrMsg: gams.control.options.ErrMsg
  • GAMS.Empty: gams.control.options.Empty
  • GAMS.ECImplicitLoad: gams.control.options.ECImplicitLoad
  • GAMS.DumpParms: gams.control.options.DumpParms
  • GAMS.DumpOpt: gams.control.options.DumpOpt
  • GAMS.Digit: gams.control.options.Digit
  • GAMS.DFormat: gams.control.options.DFormat
  • GAMS.CheckErrorLevel: gams.control.options.CheckErrorLevel
  • GAMS.CharSet: gams.control.options.CharSet
  • GAMS.LstCase: gams.control.options.LstCase
  • GAMS.CaptureModelInstance: gams.control.options.CaptureModelInstance
  • GAMS.AsyncSolLst: gams.control.options.AsyncSolLst
  • GAMS.AppendOut: gams.control.options.AppendOut
  • GAMS.AppendExpand: gams.control.options.AppendExpand
  • GAMS.Action: gams.control.options.Action
  • GAMS.GAMSParameter: gams.control.Parameter
  • GAMS.GAMSParameterRecord: gams.control.ParameterRecord
  • GAMS.GAMSRunParameters: gams.control.RunParameters
  • GAMS.GAMSSet: gams.control.Set
  • GAMS.GAMSSetRecord: gams.control.SetRecord
  • GAMS.GAMSSymbol: gams.control.Symbol
  • GAMS.GAMSSymbolDomainViolation: gams.control.SymbolDomainViolation
  • GAMS.GAMSSymbolRecord: gams.control.SymbolRecord
  • GAMS.GAMSVariable: gams.control.Variable
  • GAMS.GAMSVariableRecord: gams.control.VariableRecord
  • GAMS.GAMSWorkspace: gams.control.Workspace
  • GAMS.GAMSWorkspaceInfo: gams.control.WorkspaceInfo